Texas is the second largest state in U.S.A. based on geographical area, population and the economy. It is home to several large coastal urban areas with major industries and infrastructure supporting the fossil-fuel based energy sector. Most of the major cities on the state have been impacted by significant air pollution events over the past decade. Studies conducted in the southern coastal region of TX have identified long range transport as a major contributor of particulate matter (PM) pollution along with local emissions. Biomass burns, secondary sulfates and diesel emissions sources are comprise as the dominant mass of PM2.5 have been noted to be formed by the long range transport biomass from Central America. Thus, the primary objective of this study was to identify and quantify local as well as regional sources contributing to the PM pollution in the coastal area of Brownsville located along the Gulf of Mexico. Source apportionment techniques such as principal component analysis (PCA) and positive matrix factorization (PMF) were employed on the air quality monitoring data to identify and quantify local and regional sources affecting this coastal region. As a supplement to the PMF and PCA, conditional probability function (CPF) analysis and potential source contribution function (PSCF) analysis were employed to characterize the meteorological influences for PM events. PCA identified an optimal solution of 6 sources affecting the coastal area of Brownsville, while PMF resolved 8 sources for the same area. Biomass comingled with sea salt was identified to be the dominant contributor from the PCA analysis with 30.2% of the apportioned PM mass in Brownsville, meanwhile PMF account secondary sulfates I & II with 27.6%. the other common sources identified included, biomass burning, crustal dust, secondary sulfate, oil combustion, mobile sources and miscellaneous traffic sources.

No description available.

L'objectif de cette thèse est le développement et la validation d'un modèle numérique de la dynamique des particules en mélange externe et résolu en taille. Afin de suivre plusieurs compositions chimiques par classe de tailles, une nouvelle approche est présentée dans laquelle la composition chimique des particules est elle-même discrétisée suivant la fraction d'un ou plusieurs des constituants chimiques (e.g. suie, sulfate). Cette approche a pour but de mieux simuler l'évolution d'une population de particules à l'échelle locale et de particulariser des compositions chimiques typiques de certaines sources. Dans l'atmosphère, les particules interagissent essentiellement entre elles et avec les polluants gazeux par coagulation et condensation/évaporation. La première partie de la thèse a été consacrée à l'élaboration du modèle pour la coagulation, processus physique qui s'avère le plus complexe à modéliser selon notre approche du mélange externe. Dans un premier temps, les équations de la coagulation en mélange externe sont présentées et discrétisées suivant un nombre arbitraire de classe de tailles et de compositions chimiques. Plusieurs simulations numériques ont ensuite été effectuées avec ce modèle sur un même cas d'étude, en utilisant deux, trois et quatre composants chimiques. On vérifie à chaque fois que les résultats de la simulation numérique en mélange externe sont cohérents avec ceux du mélange interne du cas d'étude. Les résultats de ces simulations permettent d'apprécier l'effet de mélange de la coagulation qui produit, à partir de particules monocomposées, des particules bicomposées et tricomposées. Étant donné la complexité croissante d'un tel modèle, une attention toute particulière a été portée à l'implémentation numérique et à l'optimisation des algorithmes choisis. L'extension de cette approche à la condensation/évaporation constitue le prochain développement de ce modèle, nous en posons les bases théoriques en annexe. S'il existe aujourd'hui des données de mesure résolues en taille (SMPS), il n'y en a pas encore qui puissent être réellement validantes pour ce modèle de mélange externe, c'est-à-dire qui distinguent quantitativement plusieurs compositions chimiques par classe de taille. Aussi, dans la seconde partie de la thèse, nous avons envisagé le protocole d'une expérience en chambre permettant de mettre en évidence le mélange par coagulation de deux populations de particules de compositions différentes et d'apporter des données validantes pour le modèle développé. Deux séries d'expériences ont été menées, la première dans la chambre de grand volume CESAM et la seconde, dans le réacteur de petit volume de l'INERIS. La première série a mis en évidence l'homococagulation de chaque distribution polydispersée prise séparément et dans une moindre mesure, l'hétérocoagulation des deux distributions de nature différentes (NaBr et KBr) entre elles. La seconde série a montré la possibilité d'observer simultanément deux distributions monodispersées de particules de compositions différentes (CaSO4 et KBr), prérequis pour ce cas. Au final, les résultats de mesure se sont avérés insuffisants pour produire des données validantes pour le modèle, à cause du trop grand écart-type des distributions polydispersées dans la chambre de grand volume et à cause du dépôt au paroi qui domine dans le réacteur de petit volume. Des analyses au microscope électronique ont cependant attesté de la présence de particules issues de la coagulation entre les deux natures. A la suite des différentes expériences menées, nous revenons sur le protocole envisagé et proposons quelques pistes d'améliorations / The objective of this thesis is the development and validation of a numerical size resolved and externally mixed model of the particle dynamics. In order to trace several chemical compositions for each size class, a new approach is presented in which the particle chemical composition is itself discretized according to the mass fraction of one or several of its components (e.g. soot, sulfate). This approach aims to improve the simulation of the particle population evolution at local scale and to emphasize chemical compositions which are specific to some sources. In atmosphere, particles interacts essentially between themselves and gaseous pollutants through coagulation and condensation/evaporation. The first part of this thesis is dedicated to the model development for the coagulation process, which happens to be the most complex to model with our external mixing approach. First, coagulation equations in external mixing were set up and discretized with an arbitrary number of size and chemical composition classes. Several numerical simulations were then performed with this model according to the same case 6 study, using two, three and four chemical components. We checked each time that the simulation results in external mixing agreed well with those of the case study internal mixing. The results of these simulations are useful to understand how coagulation mix particles and produces, from monocomposed ones, bicomposed and tricomposed particles. Given the growing complexity of such a model, the numerical implementation has been carried out with carefullness and algorithms have been optimized. The extension of this approach to condensation/evaporation is the next development step of this model, the theoretical basis are adressed in appendix. Size resolved particle measurements (SMPS) do exist nowadays, but truely suitable data to validate the external mixing model still lack, that is to say measurements which would quantitatively distinguish several chemical compositions per size class. That is why, in the second part of this thesis, we considered the protocol of a chamber experiment allowing to highlight the mixing by coagulation of two particle populations with distinct compositions and to bring validating data for the model developed. Two series of experiments were conducted, the first one with the CESAM large volume chamber and the second, with the small reactor of INERIS. The first serie underlined the homocoagulation of each polydispersed distribution taken separately and to a lower extent, the heterocoagulation of the two distributions of different kinds (NaBr et KBr) between themselves. The second serie showed the possibility to observe simultaneously two monodispersed distributions of particles with different compositions (CaSO4 et KBr), which was required in this case. Finally, measurement results happened to be insufficiant to produce validating data for the model, because of the great deviation of polydispersed distributions in the large volume chamber and because of the dominating wall losses in the small reactor. However, some microscope electronic analysis showed evidences of particles produced from coagulation between both kind of particles. Further to these experiments, we come back to the planed protocol and propose some improvements

This study is concerned with the political impact of the Supreme Court's decisions concerning state legislative apportionment. First, an attempt is made to describe the political environment in which they were made, with special reference to the existing bases of representation in the states and the political reaction to the decisions. Secondly, the study traces the major issues relating to judicial enforcement of the apportionment standards enunciated by the Supreme Court and the modification and development of those standards that followed the initial decisions. Finally, the extent to which reapportionment has been successfully enforced by the courts may suggest some tentative conclusions about the viability and utility of the equal population doctrine as a constitutional standard, as well as some of the possible political consequences of enforcement of that standard.

A year-long study was conducted in Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day resolution was conducted at three sites from February 2009 to February 2010. Detailed organic carbon speciation was collected at 5-week resolution. A series of samples representing native soil, agricultural soil, road dust, and cattle feed lot material was collected, resuspended in the laboratory, and analyzed to provide a chemical source profile for each soil type yielding insights into unique source signatures. Observations within the chemical speciation data and subsequent modeling analysis show a strong impact from local sources at the Cowtown site where mass concentrations are highest. Source apportionment results confirm the significant impact from the cattle feedlot adjacent to the site. Chemical analysis of ambient particles and local feedlot material shows the presence of chemical marker species including phosphate which is unique to this source. Fugitive dust is a significant contributor to ambient particulate matter concentrations at all monitoring locations. Seasonal observations show higher concentrations during tilling and harvesting indicating the large role agricultural sources play on particle concentrations in this area. Chemical characterization and modeling show that re-entrained road dust is a significant factor. Fine particle modeling results indicate that concentrations are influenced significantly by motor vehicles including impacts from direct emissions including brake wear and indirect emissions including resuspended road dust. A significant fraction is also associated with crustal sources while about 5 g/m3 appears to be transported into the region from beyond the air shed. Detailed analysis of the local monsoon season indicates that monsoon rains serve to clean the atmosphere resulting in a marked decrease in ambient coarse mass and resulted in a period where local coarse PM concentrations measured at all sites became more uniform. The monsoon season also featured localized high wind events which severely increased coarse PM concentrations and often caused exceedences of the PM National Ambient Air Quality Standard.

A year-long study was conducted in Pinal County, Arizona to characterize fine and coarse particulate matter as a means of furthering our understanding of ambient concentrations and composition in rural, arid environments. Detailed measurement of ambient fine and coarse mass, ion, metal, and carbon concentrations at one-in-six day resolution was conducted at three sites from February 2009 to February 2010. Detailed organic carbon speciation was collected at 5-week resolution. A series of samples representing native soil, agricultural soil, road dust, and cattle feed lot material was collected, resuspended in the laboratory, and analyzed to provide a chemical source profile for each soil type yielding insights into unique source signatures. Observations within the chemical speciation data and subsequent modeling analysis show a strong impact from local sources at the Cowtown site where mass concentrations are highest. Source apportionment results confirm the significant impact from the cattle feedlot adjacent to the site. Chemical analysis of ambient particles and local feedlot material shows the presence of chemical marker species including phosphate which is unique to this source. Fugitive dust is a significant contributor to ambient particulate matter concentrations at all monitoring locations. Seasonal observations show higher concentrations during tilling and harvesting indicating the large role agricultural sources play on particle concentrations in this area. Chemical characterization and modeling show that re-entrained road dust is a significant factor. Fine particle modeling results indicate that concentrations are influenced significantly by motor vehicles including impacts from direct emissions including brake wear and indirect emissions including resuspended road dust. A significant fraction is also associated with crustal sources while about 5 g/m3 appears to be transported into the region from beyond the air shed. Detailed analysis of the local monsoon season indicates that monsoon rains serve to clean the atmosphere resulting in a marked decrease in ambient coarse mass and resulted in a period where local coarse PM concentrations measured at all sites became more uniform. The monsoon season also featured localized high wind events which severely increased coarse PM concentrations and often caused exceedences of the PM National Ambient Air Quality Standard.

The current problems and possible solutions surrounding United States transfer pricing regulations are discussed and studied. The schemes large multinational companies are implementing to legally evade taxes are uncovered as the financial effects to the United States Treasury and government are becoming material. The benefits for these schemes are financially advantageous for corporations as they are able to report larger profits and higher returns for investors. But this is being done at the expense of our government. Corporations are finding ways to escape the high U.S. corporate tax rate and lower their global tax liabilities by allocating income to lower tax jurisdictions. Tax havens like Ireland or Bermuda are popular to have subsidiaries which hold a corporations intangible property. Five United States Tax Court cases concerning transfer pricing are studied and the outcomes are analyzed. The current problems studied from these cases are, shipping intangible property, valuing intangible property, the arm’s length standard. The possible solutions to these currents problems are by no means easy to solve and no one revision can relieve all the problems. The arm’s length standard is the corner stone to the current problems and if the government can find a way to better enforce the standard or replace it, it will be a large step in the right direction.

This thesis analyzes the history behind reapportionment and how the task of redistricting has differed in the past decades. For the most part, there was always been a public outcry when the task was in the hands of the Legislature. Fear of political gerrymandering and the creation of safe districts was enough for people to pass a series of initiatives to try and correct the system. While many initiatives failed to pass, Proposition 11, passed in 2008, created the Citizen’s Redistricting Commission—a 14-member committee put in charge of drawing this years’ plans. This paper also looks at population trends in the past decade and takes into account the impact of the increase in Latinos in the state of California.

The European Commission is currently working on a legislative draft to harmonise the corporate income tax provisions for multinational groups of companies throughout the European Union. For that purpose the European Commission has installed a working group with the mission to draft a Common Consolidated Corporate Tax Base (CCCTB) applicable for multinational companies. As the EU member states are not willing to surrender their taxing power to the supranational level of the EU each group entity's tax base would be determined by apportionment of the group's overall taxable income according to a predefined micro-economic factor based formula whereas the group income will be calculated by consolidating earnings beforehand separately determined by each group entity (preconsolidation income). The situs state of the particular group entity would then apply its statutory corporate tax rate on the apportioned tax base. This paper evaluates the effects of this prospective apportionment procedure on any given corporate group entity and finds that the share of the group's income allocated to a particular entity using the apportionment formula does regularly not equal the pre-consolidation income of the respective group entity. The reasons for this regular observable deviation can be found on the one hand in the concept of the apportionment formula and on the other hand in the specifics of the definitions of the apportionment factors. (author's abstract) / Series: Discussion Papers SFB International Tax Coordination

Fine particulate matter (PM2.5) has been associated with adverse effects on human health, but whether specific components of PM2.5 are responsible for specific health effects is still under investigation. The complex chemical composition of PM2.5 and issues such as multi-component interactions, spatial variability and sampling/instrument error further complicates this analysis. A complementary approach to examining species-specific associations is to assess associations between health outcomes and sources contributing to PM2.5, which can provide critical information to regulators to tighten controls on sources that contribute most to adverse health effects and allows for better multi-pollutant epidemiologic analyses, as the number of source-categories is typically far less than the number of PM2.5 species. This study develops and evaluates various air quality modeling approaches for determining daily source contributions to ambient PM2.5. Results from long-term air quality simulations using an emissions-based model (Models-3/CMAQ - Community Multiscale Air-Quality model) were evaluated in terms of the model's ability to simulate short-term (e.g., daily) variability in concentrations of PM2.5 components. To examine source-specific health outcomes, an extended PM2.5 source-apportionment model, CMB-LGO (Chemical Mass Balance incorporating the Lipschitz Global Optimizer) was developed and compared with results based on other approaches such as CMB, PMF (Positive Matrix Factorization), and Models-3/CMAQ in terms of simulating the daily variability of source impacts. Based on findings from spatial and temporal analyses of tracer concentrations and source impacts, PM2.5 source-apportionment results from CMB-LGO and PMF were applied in a health-study for the Atlanta area. Despite methodological differences and uncertainties in the apportionment process, good agreement was observed between the CMB-LGO and PMF based risk ratios, indicating to the usefulness of applying apportionment methods in health studies.